Thursday, November 12, 2009

After games of 10.3, 9.7 and 12.3 in yards per attempt, he averaged 7 against Minnesota and 7.6 against Tampa Bay. You could assume from those numbers that Rodgers has been throwing deep less often and completing more of his passes in the short or medium ranges.

Well, technically, you could assume anything you want. So I guess "from a certain point of view" (Kenobi, 1983) Silverstein is doing a good job.

But there is no basis for the assumption that Silverstein makes. Yards per attempt will be affected by many other factors besides pass selection. Most critically, yards per completion will be affected by completion percentage. If you throw a 50 yard bomb on every play, and ultimately complete 15% of those passes, your "yards per attempt" with be 7.5. Jumping to Silverstein's assumption you would discern that 7.5 yards per attempt indicates that the QB is completing a lot of short passes. Clearly untrue.

Moreover, yards per attempt will be affected by a players yardage after catch. We saw this in the Cleveland game, in which Driver and Havner took short passes and ran them for 71 and 45 yard touchdowns, respectively.

As you see below, the biggest factor between games 4-6 and 7-8 appears to be completion percentage. My hunch is that Rodgers completion percentage is lower, at least in part, because he is airing out the ball even more rather than less.